Answer:
The correct answer is 57 degrees.
Explanation:
To solve this problem, we must remember that vertical angles (angles that are across from each other) are congruent, which means that they have the same measure.
In the diagram, angle 3 and angle 1 are vertical angles, so we can conclude that they have the same measure.
Therefore, m<1 = m<3 = 57 degrees.
Hope this helps!